Pusher type carrier scraper



A ril 2, 1963 Filed July 1, 1960 C. P. KNIGHT PUSHER TYPE CARRIER SCRAPER 3 Sheets-Sheet 1 Car] P Knight INVENTOR ATTORNEY Y mum A ril 2, 1963 c. P. KNIGHT 3,083,479

' PUSHER TYPE CARRIER SCRAPER Filed July 1. 1960 3 Sheets-Sheet 2 Car? 1 Knight INVENTOR BY M. W

ATTORNEY April 2, 1963 c. P. KNIGHT Pusasa TYPE CARRIER SCRAPER 3 Sheets-Sheet 3 Filed July 1. 1960 TTORNEY 3,@? 3,479 PUSJLR TYEFE CARRIER SQRAPER Carl P. Knigh 4&7 N. Service Drive, Alexandria, Va. Fiied July 1, 196d, Ser. No. 49,466 4 Claims. (Qt. 371Z6) (Granted under Title 35, Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royalties thereon.

This invention relates to a new and useful improvement in earth movers or carrier scrapers of the type used for earth digging, carrying and filling operations.

Earth moving machines of the type described generally make use of a main bowl having a forward cutting blade mounted on a wheeled frame. The main frame is pivoted at its front end to the rear of a tractor which pulls the carrier scraper during its work cycle.

In the machine of my invention a radical departure from the usual mode of operation is achieved. The tractor of my invention is used to push the carrier scraper during its work cycle. The main bowl is mounted on a wheeled frame having a forward cutting blade. The wheeled frame is pivoted at its rear end to the front of a tractor for pushing the earth mover into the digging operation and after the carrier scraper is loaded continues to push the carrier scraper toward the site at which the bowl is to eject its load.

It has long been the desire of earth moving men to cut costs of operation by reducing the required travel of the scrapers from the excavating or loading site to the unloading site. Moreover, as happens often times in earth excavation, an earth scraper will not be able to turn around at the area being excavated but will have to travel a grater distance to a cul-de-sac or turn around place.

Also, in excavation it is common practice today, in order to obtain a full load, to utilize a pusher tractor for pushing the carrier scraper as it excavates the earth. Thus resulting in added expanse by tying up a machine and man to a job that often totals many hours of doing nothing while waiting for a scraper carrier to arrive at the excavating site.

My invention has been made with the foregoing considerations in mind and have many important objectives in its creation and use.

An important object of my invention is the provision of an earth scraper which can be self propelled to a site to be excavated, pushed into the earth to obtain a full load and then either pushed forwardly to the unloading site or pulled thereto.

Another important object of my invention is the use of the pinciple of weight transfer to obtain a larger load in loading a carrier scraper without the use of a pushing tractor.

Another important object of my invention is to provide a carrier scraper which can more economically op crate in earth moving operations than conventional carrier scrapers in use today.

Another important object of my invention is to provide a crarrier scraper which will reduce materially the distance required to travel between the loading site and the unloading site, by eliminatin need for turnaround.

Other features and advantages not specifically enumerated will become apparent after a consideration of the following descriptions and the appended claims.

In the drawings, which represent a preferred embodiment of my invention:

FIGURE 1 is a side elevational view of the carrier scraper of my invention shown attached to the propelling tractor.

3&83479 Fatented Apr. 2, 1963 FTGURE 2 is a top plan view of the carrier scraper of FIGURE 1.

FIGURE 3 is a side elevational view of the carrier scraper of my invention taken on the line 33 of FIG- URE 2.

FIGURE 4 is a sectional view of the rear portion of the carrier scraper of my invention taken on the lines 4-4 of FIGURE 2.

Referring now to FIGURE 1 wherein the carrier scraper consists generally of a main bowl A, a front apron B and a main frame C. The main bowl consists of the side Walls it), a hinged bottom 12 and the inclined digging blade 14. The hinged bottom 12 extends between the side walls and has a pivotal connection 16 with the mounting of the digging blade. The digging blade extends between and is rigidly connected to the lower forward portion of the side walls. The sides of the bowl are con nected at its rear end by the wall 18. In FIGURE 3, the hinged bottom is shown in the normal carry or excavating position in the solid line and in the partly raised discharge position in the dotted line.

Spaced beams (not shown) rigidly interconnect the side walls of the bowl. The exact formation of the bowl does not form a part of my invention and is therefore not described in greater detail.

Upstanding projections 24 are formed on the side walls of the bowl at the upper portion thereof intermediate the ends, to which is pivoted at 22 the arms 24 of the apron. Thus the apron may be swung between raised and lowered closed positions relative to the digging blade 14.

The main frame C consists of two side box beams 26 and 28 which are pivotally connected to the front wheels 30 by stub axles 32 inwardly arranged on the front extremities of the beams 26 and 23. The rearward ends of the box beams are connected together in a rigid structure by the beam 34. Beams 36 and 38, rigidly attached to the box beams 26 and 28 respectively, extend upwardly therefrom at an angle at a point intermediate the ends of the box beams. A beam 41 rigidly connects the upper ends of the beams 36 and 38.

The bowl A is pivotally attached to the main frame by shafts 42 provided on the main frame at a point adjacent the attachment of the beams 36 and 38. In this respect it is to be noted that the bowl is pivoted at a point closer to its rear end than the front thereof in order to provide a proper normal overbalance in a forward direction.

The bowl can be raised and lowered about the axis of the shafts 42 by means of the cables 44. Formed on the upper front portion of each side wall 10 is an upstanding lug 4s. The cable 44 is fixed at one end to the lug 46. Extending from 46 the cable 44 is passed over a sheeve 48 mounted on the upper inner side of beams 36 and 38, then is passed around a sheeve 5t} mounted on end of the beam 34, then is passed around a fairlead sheeve 52 mounted on an intermediate portion of the beam 34. Thence it passes to a winch 54 which is operated from the power take-off of my tractor T.

Cable 65} controls the function of apron lifting and dumping. it passes from the winch 56, which is also operated from the power take-off of the tractor, around the fairlead sheeve 58 mounted on the beam 34, around the sheeve 62 mounted adjacent the rear end of the beam 26, over the sheeve 64 mounted on the beam it} by a sheeve bracket 66, around a sheeve 63 mounted on the beam 4t) centrally thereof, and under a sheeve 7t} mounted on the central portion of the apron. Thence over a sheeve '72 mounted centrally on the beam 4t) adjacent sheeve 68, over a sheeve 74 extending upwardly at the top central portion of the bowl bottom 12, to an anchorage 76 on the beam 4% adjacent the sheeve 72. The result of this reeving is that when the cable is drawn in, sheeves 68 and 70 will first be drawn together to thus raise the apron B a. short distance. By continuing to draw in on cable 60 and by reason of the weight of the apron, sheeves 74 and 72 will then be drawn together to raise the bottom 12 about the pivot-.16. After'the bottom 12 has been raised, further drawing in of. the cable will thenresult in the further raisingiof the apron.

Dependingfrom the beam. 34- is. a. push plate 80. Brace plates 82 are rigidly attached to beam 34. and the forward face of the push plate 80. A female coupling 84 of aball and. socket joint 90 is rigidly attached to the rearward face of the push plate 8% The male member 86.ofthe ball and socket joint is carried by athrust arm 88 extending. outwardly from and rigidly carried by the front structure of the tractor.

Rigidly attached tothe bottom of plate 34 at each side thereof adjacent the beams 26 and 28 is a hydraulic cylinder 92, a ram 93 extends downwardly from each cylinder andhas fixedly attached thereto at the lower portion a U-shaped yoke 94. A caster wheel 96 ismounted in the yoke by means of axle 95 carried thereby. The ram 93-is arranged to rotate in the cylinder 92.

The hydraulic cylinders 92 are operatedby a conven-. tional system (not shown) through the tractor power take-01f.

The operation of my machine is as follows: The operator oflthe tractor travels to the site being excavated by either travelling rearwardly-fwith the tractor and thus pulling the carrier scraper, or by travelling in aforward direction with respectto the tractor and thus pushing the carrier scraper. Obviously the material being excavated canthen be carriedloaded tothe site of unloading by either method of travel. When pulling the carrier scraper the arm 88 acts as a draft bar as the tractor travels rearwardly.

Assume, however, thatthe tractor is moving forwardly pushing the carrier scraperto load the bowl. In such operation the operator advances the tractor in a forward direction moving against the thrustbar 38, the carrier scraper islowered to take a cut by controlled release of the cable 44. Asthe scraper is advanced, the opposite reaction of force against theithrust, of the tractor .will cause a transfer of weightof the bowl back to the tractor, compression of cylinder 92 will cause the back of frame C to lower on caster wheels96, by this reaction. Raising or lowering the bowl will control the extent of weight transfer back to the tractor.

As thus 'will appearobvious, the weight transferred back to the tractor is .thus used to obtain a better traction and to permit the operation of thecarrierscraper to obtain a load without requiring the use of a pusher-tractor. As will also appear obvious, the. bowl when it is unloaded can also, be used to transfer its weight back to the tractor for better traction by activating the cylinders 92 to raise the caster wheels and thus permit part of theweight of r A. such undesired movement by changing the direction of movement of the tractor to-overcome the change of direction of the carrier scraper.

Other modifications and variations of the present invention will occur to those skilled in the art after a careful study of the invention which I have disclosed. For example, a two wheeled tractor could be utilized'in place of the endless type crawler tractor shown in the drawings. All such modifications and Variations which come within the spirit and scope of the present invention are intended to be included herein as fully and completely as if they had been specifically illustrated, described and claimed.

Having thus described and disclosed my invention, what is claimed as new is:

1. The combination with a prime mover of a pusher type carrier scraper comprising a frame, a bowl-pivotally mounted on said frame and onvan axis transverse to said frame having a forward digging edge and substantially parallel sides, a bottom for said bowl pivotally mounted in said bowl and turning on an axis normal to said sides of said bowl, a pivotally mounted closing apron, connecting means between the front of said' prime mover and the rear of said carrier scraper, independentsuspension means for said frame including two caster wheels mounted in hydraulic cylinders rigidly afiixed to said frame, operating means coasting to open said apron and to. raise said bottom, operating meansfor rotating said bowl, and controls in said prime mover for said opening and'closing of said apron and said bottom and for rotating said bowl.

2. The combination with a prime mover of a pusher type carrier scraper as described in claim 1 wherein said frame is inclined downwardly forward fromthe end at which is mountedsaid connection means.

3. The combination with a prime mover of a pusher type carrier scraper as described in claim 1 wherein said connecting means comprises a thrust arm rigidly aflixed to said prime mover and extending forward from said prime mover, and a ball and socket joint connecting said thrust arm to said frame of said pusher carrier scraper.

4. The combination with a prime mover of a pusher type carrier scraper as described in claim 1 wherein the operating means for opening said apron and raising said bottom comprise a winch mounted on said prime mover, a cable extending from said winch successively through a sheave mounted, on said apron through a sheave mounted on said bottom to a stationary anchor secured to said frame.

References Cited in the file of this patent UNITED STATES PATENTS 

1. THE COMBINATION WITH A PRIME MOVER OF A PUSHER TYPE CARRIER SCRAPER COMPRISING A FRAME, A BOWL PIVOTALLY MOUNTED ON SAID FRAME AND ON AN AXIS TRANSVERSE TO SAID FRAME HAVING A FORWARD DIGGING EDGE AND SUBSTANTIALLY PARALLEL SIDES, A BOTTOM FOR SAID BOWL PIVOTALLY MOUNTED IN SAID BOWL AND TURNING ON AN AXIS NORMAL TO SAID SIDES OF SAID BOWL, A PIVOTALLY MOUNTED CLOSING APRON, CONNECTING MEANS BETWEEN THE FRONT OF SAID PRIME MOVER AND THE REAR OF SAID CARRIER SCRAPER, INDEPENDENT SUSPENSION MEANS FOR SAID FRAME INCLUDING TWO CASTER WHEELS MOUNTED IN HYDRAULIC CYLINDERS RIGIDLY AFFIXED TO SAID FRAME, OPERATING MEANS COACTING TO OPEN SAID APRON AND TO RAISE SAID BOTTOM, OPERATING MEANS FOR ROTATING SAID BOWL, AND CONTROLS IN SAID PRIME MOVER FOR SAID OPENING AND CLOSING OF SAID APRON AND SAID BOTTOM AND FOR ROTATING SAID BOWL. 